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Got a tweet from a reader here who recommended The post by Rupa Subramanya Dehejia on the Wall Street Journal on Why We Need a Proper Nuclear Regulator and asked me for my opinions. Since I had intended to wait until the direction of the Fukushima tragedy becomes more clear, I decided to combine the two. If we pursue nuclear power, we must understand possible nuclear risk scenarios and do all we can to minimize risks of nuclear accidents.

Destroyed Reactor 3 building at Fukushima

As always, I am stating upfront, that I am a curious lay person and not any kind of authority. I write based on what information is available and how I understand it. I hope that these posts trigger thought around these subjects rather than provide an authoritative reference. It is not.

First, I'd like to share a useful resource to understanding this tragedy that I found on cryptome. This pretty much describes everything in the order it happened, with illustrations.

The Fukushima tragedy is nowhere near a solution, and the pretence of it not being a big deal is wearing down fast. Even as early "information" about it being not so dangerous was being released, I had raised the question of what happens to the spent fuel tanks the minute I heard about the explosions in the buildings. I had got a comment or two about how I was scare mongering and that I should read facts. Facts published by a government and company keen on a cover up or facts by a nuclear lobby not wanting to jeopardize its business. No thank you. I don't need an expert to tell me that  a bathtub is under the sky if the roof of the house is blown up.

Rubble of the reactor 3 at fukushimaThe reason for that is that the fuel in the reactor is under considerable safeguards, while the fuel in the spent pool tanks is essentially in a bathtub - that is how open it is. Agreed, that spent fuel is about as radioactive as the radioactive substances in their form in nature, but we don't live in uranium mines, do we? Nor do we spray it in the air. Doing that with natural uranium is also going to be dangerous.

Anyway, my certainty that the spent fuel tanks were in trouble was simply that the building was gone. It was near certain that the pool was now open to the sky (other than debris, of course). Normally, this shouldn't be a problem at all, because the radioactivity emitted is of particles, which have very little capacity to penetrate much and are only a problem with proximity. The water effectively traps them, and they don't get out of their pool, which is why there is absolutely no problem with keeping the pool open on the work floor.

The problem is if that water is gone. There is no longer anything trapping the radioactive particles. They are still not dangerous enough to reach very far, but the problem is that they don't need to. The particles colliding with other radioactive atoms in the fuel trigger further fission. Fission is happening all the time, but the water controls it so that it doesn't escalate to a chain reaction. With the water gone..... An uncontrolled fission chain reaction is essentially a nuclear bomb, whether it was intended as that or not. The fuel not being designed to function as a bomb will probably make it less efficient, but make no mistake, it won't prevent it from exploding or even if some controls survive, to generating enough heat to convert a lot of the radioactive matter into dust/gas.

So what? There was water in the pools, they are still safe? Nope. The residual fissions in the radioactive material are constantly generating heat. Heat evaporates water. Nuclear heat evaporates water real fast. Which is why there is such a rush to flood the spent fuel tanks with water. Even sea water, with its risk of corroding material. They cannot afford that fuel to run dry - that is the bottom line.

We have three major scare areas apart from the general lethality of the whole thing of course:

  • The fuel in Reactor 4 is not all spent. The reactor was closed for maintenance. There is nothing inside the reactor. The potent stuff that was generating electricity in reactors 1,2 and 3 is soaking in its bath tub in reactor 4. This is why we hear more news of reactor 4's spent fuel pool being flooded with sea water. Because it gets hot faster, and evaporates water faster. And no, the water is not going to cool that down. This is going to happen for a long, long time, because it is enriched still, and becuase partial exposure to air accelerated the fissions within it even more.
  • The fuel in reactor 3 is called MOX. It contains Plutonium in addition to Uranium. This plutonium is far more potent (radioactive) and it is essentially the plutonium recycled from decomissioned nuclear weapons. Plutonium is also extremely dangerous to get contaminated with, and it lasts longer than you can imagine. With a half-life of 24,000 years, that plutonium is likely to outlive mankind altogether. Got that? So, keeping that reactor from exploding is a huge priority. Good part being that the enriched fuel is inside, and while still dangerous, the spent fuel tanks have spent fuel only.
  • Reactors are leaking. First it was thought that it was only reactor two, but now it seems that its all three. Worse, the tanks storing the seawater coming out of the reactors have at least one confirmed leak, possibly more. They are leaking directly into the sea. Baaad news.

Not kidding you. We don't have a prayer of containing gas in a facility where we couldn't secure solids and liquids. Not to mention the little matter of it already being open to the elements, free to ride the breeze and go where it wants.

The government has finally given up euphimisms and has admitted that the reactors will be decommissioned (no shit Sherlock!) and buried in concrele, a la Chernobyl.

Bad news on that front too. Uh.... Chernobyl had exploded. It was a horrible, ghastly incident, and the reactor was dangerously radioactive, but there was no further action forthcoming. Encasing it in concrete helped to block the radiation. Fukushima is still a fight. The reactions are on. They are needing a phenomenal amount of controlling to keep from exploding. Unless they either explode (we don't want that) or are brought under control, the concrete idea is a fantasy. Or, if something goes wrong, we don't even have access to fix it, and the whole thing explodes, concrete and all. Just more radioactive debris than before. And its guaranteed to go wrong, because it is nowhere near stable. In fact, it is so volatile, that a large part of the work there is simply about keeping it from going into unchecked chain reaction. This is before we start discussing water. The crack in the tank that is leaking radioactive water into the sea could not be patched because the water kept washing the concrete away. How is this going to work, where we are actively dousing the reactors in water, and if we stop dousing them, or even if the concrete succeeds in setting and prevents the water from reaching the reactors, boom?

At this moment, the world has ZERO solution to this situation other than continuing the desperate fight against chain reactions from being started.

How is this relevant to India? Because natural disaster, compromised standards and calamity don't follow nationalities or national boundaries. While no catastrophe repeats itself, the scale of that danger is not impossible for any reactor gone "rogue".  I am not saying that we should stop using nuclear power. We need it. So far, we have also been lucky to not lose a single person in a nuclear accident, however small. We also are generally less prone to natural disasters (we manufacture our own). Of course, that is no guarantee, and lack of scrupulous measures has led to contamination in minor, but many incidents.

This brings me to what Rupa advocates in her article. The need for regulation that is free of vested interest. She describes it as a regulatory body and brings up two metaphors - one of a prison run by inmates, and another, less applicable, of a student grading his own marksheet. For some reason, she seems to have a thing about progressive schools, and me as an ardent advocate of unschooling will naturally find that a little "off", but I find this metaphor also runs the risk of decreasing the magnitude of risk. A student assessing himself is essentially an occurrence with minimal impact to others. This is where it differs phenomenally from the nuclear scenario today. The prison run by inmates is something that strikes more accurately at the situation, though I hardly think of our scientists as criminal. But the point the article makes comes through clearly. When someone has a reason to represent something in a certain way, that person or body cannot be counted on to be neutral from the perspective of the world in general.

It is something I brought up earlier as well, when I suggested that local bodies be trained to monitor risks to their community and given the right to call for inspections or evaluation, because they will be suffering the consequences of folly. Another idea that comes to mind is neighbouring countries also being involved in safeguards planning, training, and other non national-security aspects, because radiation contamination knows no national boundaries. Like Fukushima contaminating American shores, an incident in Pakistan can contaminate India, and an incident in India can contaminate Bangladesh.

So, what do you think? Given that India's power scenario doesn't afford us the possibility of giving up nuclear energy as a source of power, what can we do to minimize risk?

When the MD of TEPCO Mr Akio Komori weeps on National Television, we can no longer escape accepting that the plant is in big trouble.

Newly released images and video show clearly a crane that is used to handle spent fuel that is visible from the outside. Based on the normal location of the crane on the edge of the spent fuel pool, the pool, though not visible in the shots, is definitely there, open to the world.

When the owner of the fourth largest power company in the world and the largest in Asia breaks down in tears, you know how bad it is. Or you know that he probably wishes the earlier cover ups of security threats at the plants had not been exposed.

I am not one to panic. Initially, when I heard about the crisis, I went about supplementing what I remembered reading with information that would reflect happenings and risks without getting into nuclear advocacy or criticism. I shared my findings on nuclear meltdown and other nuclear risks to prevent panic.

All this has changed since the second explosion at the site. I am no longer able to pretend that it isn't serious. Not the crisis itself, but I am quite worried about the Government's approach to it. Its been quite leisurely and now, its in a panic. This doesn't help. In crisis, the authority figure being consistent is unmatched in its power to bring order and stability. Unfortunately, the US paranoia seems to have infected the world, and the Government of Japan, who had earlier been puzzled at the safety zone America recommended for its citizens in the region being three times that for locals, is now discovering how much in danger their people are.

The best help in a crisis would probably be a media blackout of the US Government response to it. Wouldn't be surprised to later discover that people headed out into radiation to escape because the US predicted the apocalypse. Or to find out that more people died of heart attacks from fear than radiation.

The world seems to have discovered it too. The people claiming that it wasn't a big deal or that nuclear energy is quite safe are mostly conspicuously silent, or their efforts now focus on how the radiation spreading vast distances is not really a risk beyond the evacuation zone. So, from saying that there would be no significant release of radiation, we have gone to explaining that the significant release of radiation isn't all that big a deal. Because we can no longer pretend that the radiation is not spreading. The West coast of the US and Russia have both registered elevated radiation levels - neither of them dangerous, but they exist and that is enough for people to hit panic levels. Might be good to remember that the Chernobyl explosion, which was definitely worse than this blew radioactive winds across Europe. Europe is thriving, thank you very much. Japan went through Hiroshima and Nagasaki and has better longevity than most places in the world - US included. The cancer rate is far lower for workers in nuclear plants than among general population - go figure!

Yes, the plant is devastated, but its hardly flimsy. Look at the destruction it is sitting in the middle of and still is sheltering its precious responsibility with considerable security under the circumstances. That's not accidental - its design.

<strong class='StrictlyAutoTagBold'>Japan</strong> Fukushimi Nuclear Reactor #4 exposed and possibly in full meltdown

Photos from the fourth reactor at Fukushima Daichi show clearly a green crane in the building. The green crane by itself may not sound like a big deal, but it is used to transfer fuel rods from the reactor to the spent fuel tank, and is standing right next to the tank. If you can see the crane, you can't see the pool, only because it is lower.

This video gives a better idea of the situation:

http://www.youtube.com/watch?v=gTZ9C42mOPM

It is just as exposed. Check out the picture  of the reactor from inside (before the explosion, of course).

Spent fuel pool inside reactor

The rods are in the pool, as we see. The water itself forms a barrier while it keeps the rods cool as well so that the people can work safely, with reasonable precautions.

The fuel rods stay 'hot' for quite some time post being removed, and it takes several years before they can be considered safe to be packed "dry". This water is cooled regularly to take away the heat from the decay and the water levels are managed to that the rods are always submerged.

What likely happened was that when the cooling systems failed after the earthquake and Tsunami, while the water meant that there was no immediate crisis, it did start heating up. The rods themselves were not all that old out of 'action', having been removed about three months ago, so the decay heat, while not the inferno of an active reactor, was still enough to start reducing the water in the fuel tanks.

Once the fuel rods got exposed and thus not cooled at all, the heating only picked up pace. The temperature for the zirconium around the uranium pellets to melt is about 1200 deg. Once this starts, we are in the process for a meltdown, and the mass gets increasingly difficult to manage.

The zirconium reacts with the water at a high temperature and gets oxidized and releases hydrogen gas (remember the hydrogen related experiments in school?). The thing is that hydrogen is highly reactive, and once vented, combines "violently" with the oxygen in air to form water. Water, of course is not dangerous, but the problem is that the explosion blows the building apart, and the radioactive particles contained in the steam are dangerous. This is actually the good part, because with the fuel rods exposed, they are able to release radioactivity directly into the air.

This, described above is the problem at plant 4. We have had the explosion, the damaged wall only means even less barrier from the radioactive substances, and we see that crane from outside, which is standing next to the spent fuel tanks. Do the math. If there is water, its well on its way to becoming steam.

And the biggest problem with this situation is the combination of the limitations of operations due to radioactivity and the number of reactors needing to be pulled back from the 'edge'. The most dangerous by far are Reactor 3 and 4. Reactor 4 because its wide open to the world, and the only way to cut off that radiation is going to be getting those rods underwater and keeping them there. Reactor 3, because it contains Plutonium, which is really bad news. So tell me again who had the bright idea of recycling nuclear weapons to produce the MOX fuel? Sigh. Its probably a great idea. No one could predict this. Regardless, this stuff is something that would be far more complicated to mop up, so the attempt is to keep it in, where it belongs.

There are engineers discussing the possibility of burying the reactors under tons of concrete, a la Chernobyl. However, that is for the future and more to prevent further escape of radiation, and it can be done in Fukushima, but its not much use with our current priority - getting those reactors stone cold. Without that happening, we are risking fission and explosion rather than simple leaks, however radioactive. Also, it isn't like fission needs oxygen that pouring concrete on it will smother it. It won't. Plus, the heat from the still hot and heating fuel will mess up the concrete, while the concrete messes the reactor, and only create much more radioactive debris to tidy. The proximity of the reactors is another complication they will have to work around when they do it. I don't think there is any question of "if" any more.

US and UK have advised their citizens to give the area a wide berth - 50 miles. Japan's zone of course is still 20km, which is not enough, but residents till 30km are being asked to remain indoors, which should protect them too, with precautions. For all the hysteria in the media, there seems to be little actual data to support sustained levels of dangerous radiation. That is not reassuring only because the Government of Japan seems to increasingly become opaque, so we don't know if its the whole story.

The name Chernobyl cropping up constantly doesn't help either, because one of the main reasons Chernobyl had to be evacuated was the radioactive material that spewed out of the reactor and the vast quantities of radioactive dust from the burning graphite (in other words, radioactive soot). There is no way to clean the ground of each of these gazillions of pieces which will keep emitting radioactivity long after you and I are gone. This is very different from venting a little radioactive steam, or contamination. Even if radioactive material has been leaked, as long as its on the reactor site, and not blown to bits and scattered over entire continents, there is no reason why it can't be decontaminated later.

Yes, the situation is dire, it is critical. But not because it can get to a Chernobyl scale. It is critical, because we are trying to contain damage to a minimum and without electricity, the safeguards built into the reactor are failing. Even if they totally fail, Chernobyl is extremely unlikely. That was  a situation where there was no containment at all. There was no precedent, there was far less technology. Japan has a crisis only because it doesn't want any abandoned zone at all, or, a very tiny one. So far, there doesn't seem to be any radioactive debris that would make the area unlivable.

The danger for the people largely will "switch off" once the fuel is isolated. Radioactive debris on the other hand will send out radiation - mostly contaminating through becoming a part of the place itself - the whole area will have to be isolated.

However, and I'm not saying this just to make you feel better, there are many good things happening as well. There is now a good chance that this thing will be under control soon.

  1. The idea of the fire trucks spraying water directly on the tanks right through the hole in the wall seems to be working.
  2. Surveillance from a helicopter also showed that the tanks were not completely empty. Not that it means anything particularly good right now while the rods stand exposed, but it will mean that much less water to fill in to submerge rods.
  3. Electricity has reached the plant from the grid.Power has been restored at the plant, though it will still mean a lot of testing before the cooling systems go online. This is good, because it means that instead of exhausted workers using puny efforts fighting upstream of huge odds, we can engage the pumps and cooling systems that were designed precisely for this job. This will help make the cooling really fast, as well as free up workers from maintaining to recovering damage.

What remains to be seen is how far the radioactive contamination spreads before this show comes to a stop.

My bet is that if the electricity brings the pumps back online and some of the cooling systems work at least, the rest will be a "recovery without incident". If not, then its going to be an uphill struggle. With the electricity there, the choices are considerably expanded, but they will still have to be tried and tested. That takes time. But one way or the other, the way ahead is all about getting the fuel underwater, cooled and isolated. In that order.

In the meanwhile, while I understand that the Japanese are angry with the government and TEPCO for the risk they are facing, it isn't the workers putting them at risk. The workers are volunteering their lives away to keep them safe, and they deserve some acknowledgment for what they are doing. I want to criticize some Japanese who have been quoted in news as saying that the workers battling the reactors are just doing their jobs that they are paid for. In saying this, they show how utterly dehumanized their world is. Their words are an embarrassment to them, not to the country, and certainly not to the workers who are fighting death each moment - explosion, accident or radioactivity. I feel quite certain that this arrogant person cannot afford to foot the bill for the things he claims have been paid for. He reminds me of the people shooting at the rescue helicopters after Hurricane Kartina.

To end this post, I want to throw in my estimation of what will happen. First, I think that since at least the spraying water from fire engines is working, it will be continued while more robust solutions are searched. Very likely, some electricity powered solution that can be switched on and left alone will happen, at which point everyone can forget about this while it cools down while the employees at the plant get around to fixing leaks and other problems. It will happen within hours if the cooling systems are working when they get electricity, or in another day if something new is brought in.

I think the residents in the immediate vicinity may not be allowed to return home, but the remaining will, once the radiation leaks are stopped, and any possibility for recurrence is prevented.

Here is to Japan and its spirit to live, to endure, and most of all its incredibly pragmatic attitude. I leave you with a cartoon for Kids to understand what's up with Fukushima. It is clearer about what is happening than many detailed accounts. Don't miss this.